Catalytic asymmetric de novo construction of dihydroquinazolinone scaffolds via enantioselective decarboxylative [4+2] cycloadditions was written by Lu, Yi-Nan;Lan, Jin-Ping;Mao, Yu-Jia;Wang, Ye-Xin;Mei, Guang-Jian;Shi, Feng. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2018.Safety of (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine This article mentions the following:
The first de novo construction of enantioenriched dihydroquinazolinones via an intermol. strategy was established. This approach also represented the first catalytic asym. [4+2] cycloaddition of vinyl benzoxazinanones with sulfonyl isocyanates, which afforded chiral dihydroquinazolinones in high yields and excellent enantioselectivities (up to 98% yield, 99 : 1 er). This reaction not only confronts the great challenge in de novo construction of enantioenriched dihydroquinazolinone skeletons, but also advances the chem. of decarboxylative cycloadditions involving vinyl benzoxazinanones. In the experiment, the researchers used many compounds, for example, (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3Safety of (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine).
(11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3) belongs to chiral phosphine ligands. Although many reactions require more nucleophilic trialkylphosphines as catalysts, only a few chiral trialkylphosphines are available. Trivalent phosphorus compounds called phosphines have a tetrahedral electron-group geometry which makes them structurally analogous to amines.Safety of (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine
Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis